I agree on the Pufferhead Stuff cc pack, there are several nice cc in there!
I also tried to use the brittpinkiesims's Harry Potter mod packs, there are several interesting stuff in there such as traits for the four Hogwarts houses, custom pictures for clubs or a working sorting hat, or lots of decorative objects copied from the movies. It was very nice, but I suspect that some of the included files could be broken now because I never managed to use the sorting hat and I was getting some "last exception errors" while having it in my game. It sort of make sense, I didn't manage to find any recent update to those cc packs, but it's also a pity because it seemed to be very well done...
